Liquid dispenser



Ml'ch 25, 1957 E. w. E. KAMM 2,786,602

LIQUID DISPENSER Filed June 15, 1953 IN VEN TOR.

United States Patent LIQUID DISPENSER Edmund W. E. Kamm, Fort Wayne, Ind., assigner to Bowser, Inc., Fort Wayne, Ind., a corporation of Indiana Application June 15, 1953, Serial No. 361,731

13 Ciaims. (Cl. 222-59) This invention relates to a Iliquid dispenser. More speciiically, it relates to a dispenser for volatile liquids.

In recent years the vapor pressure of motor car fuels has lbeen increasing so that the ordinary dispenser which comprises a pump, disposed in a pedestal, located on the service island of the usual filling station, becomes less effective than heretofore in withdrawing liquid from the underground tank and dispensing it to the automobile fuel tank in hot Weather.

It is a well known fact that the rotary pumps used 1n such -dispensers will develop relatively high vacuums and that the gasoline, which is disposed in relatively long runs of pipe under, but relatively close to the surfaces of the ground and filling station drives, becomes warm on hot days so that the application of the high vacuum causes the gasoline or constituents thereof to vaporize. The gas thus produced tends to satisfy the vacuum produced by the pump to the extent that the total lift required to raise gasoline from the tank and pass it through the substantially horizontal runs cannot be produced by the pump and the system fails to -operate or operates in spurts.

The lift required to raise the gasoline from `the tank to the level of the `substantially horizontal runs (which do have an inclination or fall toward the tank, but which are hereinafter referred to as -horizontal) varies, `but is often between 6 and l2 feet. Any means which would reduce this lift would assist in increasing the ability of the main pump to maintain flow or to reestablish ow after it had once been stopped.

Further, since the liquid contained in the tank is usually cooler than that in the horizontal pipes, the introduction of such liquid into the horizontal pipes will assist in reducing Vaporization and will promote the reestablishment of flow by the main pump.

The principles of the air lift pump are old and well known and the operation is predicated upon Vthe fact that a column of mixed liquid and air weighs less than a column of solid liquid and can therefore rise in a pipe to a greater height under a given pressure dilerential. By the same token, less vacuum would -be required of the main pump to raise a column of mixed liquid and air `through a predetermined distance `than to raise a solid column through the same distance.

Usually when the vaporization in a suction line begins lto disable the pump, there will be intermittent slugs of gas and liquid arrive at lthe pump. The gas, of course, reduces the pumping efficiency since gas is elastic. It also tends to dry the pump so that the liquid seal is lost and the capacity of the pump is further lowered. On the other hand, when a slug of liquid reaches the pump, the ecieucy of the pump is restored due to the inelasticity of the liquid and the rewetting of the pump.

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Since gasoline is a hazardous liquid and since the mix ture of air with gasoline vapor could easily produce an Vexplosive mixture, it is obvious that the use of air as a lifting gas isnot tolerable. Accordingly, it is an object of the invention to utilize the gas which is pumped by the main pump for eliecting the lift.

Further, since it would be undesirable to introduce gas into the pump suction lline during periods when the pump is delivering a large percentage of solid liquid, it is an object of the invention to provide means for interrupting the gas supply under such conditions.

These and other objects will become apparent from a .study of this specification and the drawings which are attached hereto, made a part hereof and in which:

Figure 1 is a schematic view of the entire pumping and electrical systems.

Figure 2 is a view of the gas control mechanism.

Referring to Figure 1, the numeral 1 represents the underground tank in which the suction pipe 3 usually terminates near lthe bottom. The pipe is usually fitted with a foot valve 5 and is connected by a swing joint 7 to the horizontal run 9 of the suction line. The other end of 9 is connected Iby another swing joint i1 to the suction stub 13 which is connected by a union 15 to the suction 17 of the positive displacement type of pump t9 which is usually of Isome rotary type and is provided with a bypass 20. This pump is referred to herein as the main pump and is driven by an electric motor 2l.

The discharge pipe 23 from the pump terminates in the gas separator '25 which has a gas outlet at the top comprising a restricted port 27 which communicates by way of conduit 29 with the float chamber 3i.

The gas separator has a liquid outlet which communicates with the usual meter 3d, which in turn drives the register 35 which may be of any desired resettable type. The discharge line 37 from the meter passes through the combined check and relief valve 38 and sight glass 39 and terminates in a hose 4l which is tted with a nozzle 43. The latter has a self-closing valve i5 which is operable 'by a trigger 47. v

Referring again to the float chamber 3l, the bottom of the chamber communicates through tube 4.19 with the ,line V17 on the suction side of the pump. The inlet of the tube is controlled by a valve 51 which is actuated fby a float 53 and linkage 55. The chamber is Vented to atmosphere by vent 56.

A hose hook 57 normally supports the nozzle and a switch lever 59 occupies its switch-oit position when the nozzle is on the hook. The lever 59 is connected by a suitable linkage 61 to a switch 63 on the motor The power main 65 is connected through the switch 63 to motor 21 so that as the switch lever is raised and lowered, the motor will start and stop. A suitable reset, interlock mechanism 67 is provided to enforce the resetting of the register 35 before the switch can be closed.

The structure thus far described is conventionai and operates as follows. When the register has been reset, the interlock mechanism will free the switch lever 59. The nozzle 43 is removed from hook and the lever 59 is raised. This closes switch 63 and starts the motor 21 and ptunp 19.

Under normal conditions, the pump will raise liquid through the foot valve S, pipes 3, 9, 13, i7 under vacuum and `discharge it under pressure through pipe 23 into the gas separator. Any gas entrained in the liquid will be separated and solid liquid will be forced out through 3 meter sight glass 39, hose 41 and nozzle 43 to the automobile tank.

The gas, mixture of gas and liquid, or, if no gas is present, liquid is forced through orifice 27 and tube 29 into the chamber 31 where further separation occurs and the gas will pass out the vent 56 while liquid is returned to the suction side of the pump through valve 51 and tube 49.

Should gas be present in the suction line, it will be drawn into the pump and discharged into the separator as described above, but if the rate of entrance or formation of the gas in the suction line equals or exceeds the rate at which the gas is removed by the pump, no liquid will be delivered and the system is said to be vapor locked. The pump will dry, heat and wear if its oper-ation is continued and may eventually fail mechanically.

The rate of formation of gas in the lines is a function of the temperature and the vacuum in the line. Liquid at a given pressure will vaporize at a predetermined temperature and at a lower temperature if the Vacuum is increased (that is, the pressure is reduced). Accordingly, since the temperature is not controllable, anything which can be done to decrease the vacuum required to lift the liquid to the pump (increase the pressure) would raise the temperature at which vaporization occurred and would assist in maintaining the llow of liquid or, if it is interrupted, would assist in starting the flow again.

This function is accomplished by providing a 3-way, piston type valve 5S in the vent 56, which is normally open to atmosphere but which may be shifted by the solenoid 69 to a position in which the vent is connected in communication with the tube 73 which returns to the tank 1 and enters the suction line 3 just .above the foot valve. The tube 73 may be a flexible or bendable tube, such as a copper tube and may be inserted through the interior of lines 3 and 9 or 3, 9 and 13 if desired to facilitate installation.

The solenoid is connected to the main 65 by switch 63 and wire 75 and to main 66 by way of wire 77, selector switch Sil, manual switch 79 and switch 63. A spring 81 is utilized to hold the valve in its venting position when the solenoid is deenergized.

In this structure, when it is noted that the pump is delivering liquid at a reduced rate, which is clearly perceptible at the nozzle or at the vent 56 where the discharge of gas is audible, the operator may close switch 79. This will energize solenoid 69 and shift the valve 58 to switch the vent from the atmosphere to the tube 73.

Since the gas being discharged by the pump is under substantial pressure, it will be forced into the column of liquid in pipe 3, at the bottom thereof, and will raise the level of liquid in the pipe and thus, in effect raise the pressure in the suction system. The lift created by this addition of gas to the column will ordinarily prevent vapor lock and will maintain liquid liow beyond the point where it would otherwise cease entirely or it will make it possible to obtain flow (prime) on starting the pump where otherwise no flow of liquid would be obtained because the pressure in the line is increased.

Obviously, of course, the liquid flow will not be equal to the normal liow obtained with a solid liquid column since a portion of the capacity of the pump is used to move gas. However, dispensing at a reduced rate is preferable to total interruption.

lt often occurs that after the pump has operated for a short while, as in making large deliveries, the cooler gasoline upon entering the pipe reduces the temperature so that vapor lock will not occur. ln such case the operator can secure full flow by reopening the switch 79.

This deenergizes solenoid 69 and restores the atmospheric vent while closing pipe 73 and the dispenser is thereby restored to normal condition so that a solid ow of liquid will be attained as soon as the entrained gas is eliminated by the separator.

rlihe passage of liquid from the chamber 31 back through line 49 to the suction side of pump 19 assists in keeping the pump primed and to insure that solid liquid rather than a mixture of liquid and gas is returned to the pump, the discharge from tube 29 enters the chamber 31 from the bottom and preferably above the center portion of the chamber.

It is, of course, quite obvious that valve 5S may be manually operated instead of power operated if desired.

1n the event `a fully automatic control for the vent valve is desired it is possible to insert in the main pump discharge line 23, preferably between the pump and the inlet to the by-pass, a liquid liow sensing device which is herein exemplied as a check valve 81 which is loaded slightly so that it will open when a substantial flow of liquid passes in the proper direction through the pipe. The valve is preferably provided at 83 with perforations of suitable area such that the valve will pass substantially the full gas output of the pump, but will be raised by either a. stream or a slug of liquid or a flow of liquid with entrained gas. Any other suitable liquid flow sensing device may of course be employed.

A magnet or armature 85 is mounted, preferably on the stem of the valve and cooperates with a complementary magnet or armature 87 on the lever 89 of switch 91. The lever is pivotally mounted at 93 in the case 95 and the leads 97, 99 are connected in series in line 77 in place of switch 79 by selector switch 80. The switch 91 is preferably a mercury type of switch and is held normally closed by the weight of element 87. The switch 91 thus remains closed as long as valve 81 remains closed, but as valve 81 opens, the element 85 raises the element 87 and opens switch 91.

The lines and 77 are preferably connected between switch 63 and motor 21 so that there Will be no current in the solenoid when the pump is not running.

Operation The operation of the modified form, after selector switch is set to cut switch 91 into line 77, is as follows:

The switch 63 is operated to start motor 21 and pump 19. So long as liquid is being pumped by the pump, Whether it is being by-passed or whether it is being dispensed, the valve 81 is held open and switch 91 is tilted to its open position.

As soon as the pump `dispenses gas in sufficient quantities to enable the ow of fluid to pass through ports 83, the valve will close and switch 91 will close to energize the solenoid 69. This will in turn shift valve 58 so that the gas discharged by the pump will be conducted to the bottom of pipe 3 and will be used to lighten the column of liquid as described above.

As soon ias a sufficient quantity of liquid is pumped to open the valve 81, the switch 91 is opened and gas is expelled to atmosphere by the valve 53. Gas is thus applied to the suction line 3 as needed to aid the pump and is automatically cut off as soon as it is not required.

The system is safe from the standpoint that there is no oxidant being added to the combustible materials to create an explosive mixture while at the same time the vapors which are under pressure and would be discharged to atmosphere are utilized to aid the main pump which is operating under adverse conditions.

It is obvious that various changes may be made in the form, structure and arrangement of parts without departing from the spirit of the invention. Accordingly, applicant does not desire to be limited to the specific embodiment disclosed herein primarily for purposes of illustration; but instead, he desires protection falling fairly within the scope of the appended claims.

What I claim to be new and desire to protect by Letters Patent of the United States is:

l. ln a dispensing system comprising a storage tank, a suction pipe in said tank terminating near the bottom thereof, a pump connected to the suction pipe, power means for driving the pump, a by-pass for the pump, a

gas separator having a restricted gas outlet, a pump discharge line connected to receive the tiuid discharged by the pump and communicating with said separator, a meter, said meter adapted to be in direct communication with the separator for receiving liquid therefrom, a dispensing lineconnected to said meter for receiving metered liquid therefrom, said dispensing line terminating in a hose provided with a nozzle having a normally closed valve, a back pressure valve disposed in said dispensing line, a separati-on chamber connected to receive the fluid discharged from the gas outlet of the separator and a vent for said chamber, the improvement which comprises a tube connected to said vent and terminating adjacent the bottom end of the suction pipe in the tank so as to discharge gas under pressure from said separation chamber into the suction pipe.

2. In a dispensing system comprising a storage tank, a suction pipe in said tank terminating near the bottom thereof, a pump connected to the suction pipe, power means for driving the pump, a by-pass for the pump, a gas separator having a restricted gas outlet, a pump discharge line connected to receive the fluid discharged by the pump and communicating with said separator, a meter, said meter adapted to be in direct communication with the separator for receiving liquid therefrom, a dispensing line connected to said meter for receiving metered liquid therefrom, said dispensing line terminating in a hose provided with a nozzle having a normally closed valve, a back pressure valve disposed in said dispensing line, a separation chamber connected to receive the duid discharged from the gas outlet of the separator and a vent for said chamber, the improvement which comprises a three way valve connected to said vent and settable either in a first position in which it connects the vent to atmosphere or in a second position in which it connects the vent to a tube, said tube terminating adjacent the bottom end of the suction pipe in the tank so as to discharge gas under pressure from said separation chamber into said suction pipe and means for selectively setting said valve.

3. The structure as defined in claim 2 in which said selective valve setting means -comprises means for normally urging said valve toward the first position and means for moving the valve to and holding it in the second position.

4. The structure as defined in claim 2 in which the selective valve setting means comprises means for normally urging said valve to the trst position and means including a motor for moving the valve to and holding it in the second position.

5. The structure as defined in claim 2 in which the selective valve setting means comprises means for normally urging said valve to the rst position, means including a motor for moving the valve to and holding it in the second position and means responsive to the flow of liquid in said pump discharge line for rendering said motor ineffective.

6. The structure as defined in claim 2 in which the selective valve setting means comprises means for normally urging said valve to the first position, means including a motor for moving the valve to and holding it in the sec-ond position and means responsive to the flow and absence of tiow of liquid in said pump discharge line for rendering said motor ineiective and effective respectively.

7. The structure as defined in claim 2 in which the selective valve setting means comprises means for normally urging said valve to the first position, means including a motor for moving the valve to and holding it in the second position and means responsive to lthe iiow and absence of flow of liquid in said pump discharge line for rendering said power means ineffective and efective respectively, said responsive means being disposed in said line between the pump and the connection of the lay-pass with said discharge line.

8. In a dispensing system comprising a storage tank, a suction pipe in said tank terminating near the bottom thereof, a pump connected to the suction pipe, power means for driving the pump, a by-pass for the pump, a gas separator having a restricted gas outlet, a pump discharge line connected to receive the iiuid discharged by the pump and communicating with said separator, a meter, said meter adapted to be in direct communication with the separator for receiving liquid therefrom, a dispensing line connected to said meter for receiving metered liquid therefrom, said dispensing line terminating in a hose provided with a nozzle having a normally closed valve, a back pressure valve disposed in said dispensing line, a separation chamber connected to receive the Huid discharged from the gas outlet of the separator and a vent for said chamber, the improvement which comprises a tube connected to said vent and terminating in the suction pipe so as to discharge gas under pressure from said separation chamber into the suction pipe.

9. The structure as defined in claim 2 in which the selective valve setting means comprises means for normally urging said valve to the first position, means including a motor for moving the valve to and holding it in the second position, means responsive to the flow of liquid in said pump discharge line for rendering said motor ineffective and a common switch for controlling the motor and the power means.

l0. The structure as defined in claim 2 in which the selective valve setting means comprises means for normally urging said valve to the rst position, means including a solenoid for moving the valve to and holding it in the second position and means responsive to the tlow Iand absence of flow of liquid in said pump discharge line for rendering said solenoid ineffective and etiective respectively.

ll. The structure as defined in claim 2 in which the selective valve setting means comprises means for normally urging said valve to the first position, means including a motor for moving the valve to and holding it in the second position and sensing means for sensing the flow and absence of ow of liquid in said pump discharge line for rendering said power means ineffective and efective respectively, said sensing means being disposed in said line between the pump and the connection of the by-pass with said line.

12. In a dispensing system comprising a storage tank, a suction pipe in said tank terminating near the bottom thereof, a pump connected to the suction pipe, power means for driving lthe pump, a by-pass for the pump, a gas separator having a restricted gas outlet, a pump discharge line connected to receive the fluid discharged by the pump and communicating with said separator, a meter, said meter adapted to be in direct communication with the separator for receiving liquid therefrom, a dispensing line connected to said meter for receiving metered liquid therefrom, said dispensing line terminating in a hose provided with a nozzle having a normally closed valve, a back pressure valve disposed in said dispensing line, a separation chamber connected to receive `the fiuid discharged from the gas outlet of the separator and a vent for said chamber, the improvement which comprises means for supplying gas under pressure to lift the level of liquid in said suction pipe, said means including a tube inserted through a portion of the suction pipe and terminating adjacent the lower end of said pipe and directed so as to dispense the gas into the pipe.

i3. In a dispensing system comprising a storage tank, a suction pipe in said tank terminating near the bottom thereof, a pump connected to the suction pipe, power means for driving the pump, a by-pass for the pump, a gas separator having a restricted gas outlet, a pump discharge line connected to receive the fluid discharged by the pump and communicating with said separator, a meter, said meter adapted to be in direct communication with the separator for receiving liquid therefrom, a dispensing line connected to said meter for receiving metered liquid therefrom, said dispensing line terminating in a hose provided with a nozzle having a normally closed valve, u back pressure valve disposed in said dispensing line, a separation chamber connected to receive the uid discharged from the gas outlet of the separator and a vent for said chamber, the improvement which comprises means for supplying gas under pressure to lift the level of liquid in said suction pipe, said means including a tube inserted through a portion of the suction pipe and termi- References Cited in the le of this patent UNITED STATES PATENTS Peter Oct. 30, 1934 Wade Nov. 17, 1936 

